EP1802849A1 - Compact compliant centering support for roller bearing having squeeze film damper - Google Patents
Compact compliant centering support for roller bearing having squeeze film damperInfo
- Publication number
- EP1802849A1 EP1802849A1 EP05811866A EP05811866A EP1802849A1 EP 1802849 A1 EP1802849 A1 EP 1802849A1 EP 05811866 A EP05811866 A EP 05811866A EP 05811866 A EP05811866 A EP 05811866A EP 1802849 A1 EP1802849 A1 EP 1802849A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- support
- centering
- bearing
- centering support
- rotor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
- F16F15/02—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems
- F16F15/023—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems using fluid means
- F16F15/0237—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems using fluid means involving squeeze-film damping
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D25/00—Component parts, details, or accessories, not provided for in, or of interest apart from, other groups
- F01D25/16—Arrangement of bearings; Supporting or mounting bearings in casings
- F01D25/162—Bearing supports
- F01D25/164—Flexible supports; Vibration damping means associated with the bearing
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C27/00—Elastic or yielding bearings or bearing supports, for exclusively rotary movement
- F16C27/04—Ball or roller bearings, e.g. with resilient rolling bodies
- F16C27/045—Ball or roller bearings, e.g. with resilient rolling bodies with a fluid film, e.g. squeeze film damping
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C19/00—Bearings with rolling contact, for exclusively rotary movement
- F16C19/02—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows
- F16C19/04—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for radial load mainly
- F16C19/06—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for radial load mainly with a single row or balls
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C2360/00—Engines or pumps
- F16C2360/23—Gas turbine engines
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T50/00—Aeronautics or air transport
- Y02T50/60—Efficient propulsion technologies, e.g. for aircraft
Definitions
- This invention relates to turbomachine, and more specifically, to the bearing support assembly that transmits the vibration force from the rotor assembly to the support structure.
- a turbomachine includes rotating components such as a fan, a compressor, and a turbine.
- the components are clamped either by a shaft or by bolted flange joints into a rotor assembly.
- forces are transmitted from the rotor assembly to the support structure.
- a film of oil (“squeeze film”) may be confined between the rotor assembly and the support structure.
- the oil in the squeeze film is under pressure and acts as a damper.
- Adequate damping requires that the squeeze film not be too thick or too thin.
- the rotating rotor assembly may not remain concentric, with respect to the squeeze film cavity, because of rotor assembly movement during acceleration, deceleration, or steady state operation.
- various conventional designs attempt to use a centering feature to maintain a uniform squeeze film damper thickness.
- the bearing appears to comprise a squeeze film damper situated at an annular contact surface between an outer bearing race and an outer structural component.
- the Bos patent does not appear to disclose an apparatus or method for centering a rotor or eliminating maneuver deflection of the rotor.
- the Bos patent does not appear to disclose an apparatus or method for providing additional viscous damping.
- an apparatus for supporting a rotor assembly in a turbomachine comprises a shaft supported by a bearing assembly wherein the bearing assembly contains one rolling element; a centering support surrounding the bearing assembly with interior and an exterior bumpers; and a bearing support housing surrounding the bearing assembly and the centering support, comprising a bearing support assembly.
- the bearing support assembly may then be attached via a support structure (such as an engine case or frame) to the turbomachine.
- an apparatus for supporting a rotating assembly in a turbomachine comprises a shaft supported by at least two bearing assemblies, wherein the bearing assemblies each contain one rolling element, a centering support surrounding the bearing assembly, with an exterior bumper and an interior bumper; and a bearing support housing surrounding the bearing assemblies and the centering support, comprising a bearing support assembly.
- the bearing support assembly may then be attached via the support structure to the turbomachine.
- an apparatus for supporting a rotor assembly in a turbomachine comprises a shaft supported by a bearing assembly, containing a rolling element, an inner race, and an outer race, a centering support, surrounding the bearing assembly with an exterior bumper and an interior bumper; and a bearing support housing surrounding the bearing assembly; and the centering support comprising a bearing support assembly.
- the bearing support assembly may then be attached via the support structure to the turbomachine
- an apparatus for supporting a rotor assembly in a turbomachine comprises a shaft supported by at least two bearing assemblies, wherein the bearing assemblies each contain one rolling element, an inner race, and an outer race; a centering support surrounding the bearing assemblies, with exterior and interior bumpers.
- a squeeze film damper may be located in parallel with the centering support, between the bearing assembly outer diameter and the bearing support housing inner diameter, with an oil supply provision contained therein for the delivery of lubricant through an annular groove to the squeeze film damper.
- the bearing support assembly may then be attached via the support structure to the turbomachine.
- a method for rotatably supporting a rotor assembly with a support structure comprises mounting a bearing assembly for supporting a rotor assembly within a movable member; suspending the movable member from the support structure upon at least two bearing assemblies; establishing a squeeze film damper between the movable member and the support structure; and centering the movable member with a centering support, wherein the centering support comprises exterior bumpers and interior bumpers.
- Figure 1 is a cross sectional view of a turbomachine, according to an embodiment of the present invention.
- Figure 2 is an isometric view of the centering support of Figure 1 ;
- Figure 3 is an expanded view of Area A of the centering support of
- Figure 4 is a flow chart of a method for rotatably supporting a rotor structure, according to an embodiment of the present invention.
- the present invention provides a centering feature to the bearing of a turbomachine (such as found in aircraft, land vehicles, space craft, generation equipment, and other high speed rotating equipment uses) that eliminates unstable vibrations and dampens synchronous vibrations.
- a turbomachine such as found in aircraft, land vehicles, space craft, generation equipment, and other high speed rotating equipment uses
- the present invention provides a compact compliant centering support for the squeeze film damper interfaces between a component, such as a bearing assembly outer race, and an outer support structure (such as an engine case or frame).
- the compact design of the present invention may be lightweight and inexpensive and may be retrofitted easily to an existing turbomachine, such as a turbomachine, for improved rotor dynamic performance.
- the compact compliant centering support squeeze film damper may be comprised of a ring with bumpers spaced around the circumference at the inside and outside diameters to form spring elements between the bumpers.
- the centering support may lift the rotor inside the squeeze film damper cavity and may eliminate rotor weight effect on the damper performance.
- the centering support may be situated between a bearing support housing and an outer race of a roller or ball bearing.
- the ring may be offset in the vertical direction to center the rotor under 1 g deflection to eliminate a rub at the 6 o'clock location of a rotating component shroud. Tangential grooves may be provided on the outer bumpers to allow oil to squeeze out when the ring is deflected to provide additional viscous damping.
- the outer bumper height may be controlled to limit maneuver deflection of the rotor.
- the present invention further provides an apparatus for supporting a rotor assembly in a turbomachine comprising a shaft supported by a bearing assembly, a centering support surrounding the bearing assemblies, with exterior and interior bumpers and a bearing support housing surrounding the bearing assemblies and the centering support comprising a bearing support assembly.
- the support apparatus of the present invention is unlike a conventional supporting apparatus that lacks an apparatus or method for centering a rotor or eliminating maneuver deflection of the rotor.
- the conventional support apparatus also does not comprise a structure for additional viscous damping, such as the tangential grooves of the present invention.
- the bearing support assembly is then attached via the support structure to the turbomachine.
- the present invention provides a turbomachine 10, such as a compressor and turbine, or a turbocharger, which may be located aboard an aircraft, missile, spacecraft, tank, turbocharger, and the like.
- a bearing support housing 14 may be connected to a support structure 12 via pilots, studs and nuts (not shown).
- the bearing support housings 14 may surround two or more bearing assemblies 46 and the bearing support housing 14 may accommodate a squeeze film damper 24 in parallel with a centering support 26 and may have an oil supply provision 50 for the delivery of lubricant (such as oil) through an annular groove 52 to a squeeze film damper 24.
- Two or more bearing assemblies 46 may support a shaft 16.
- the bearing assembly 46 may include a rolling element 22, such as a ball or a roller, an inner race 18, and an outer race 20.
- the inner race 18 may be fixed to the shaft 16.
- the centering support 26 may be situated between the bearing support housing 14 and the outer race 20 of the bearing assembly 46, including a bearing support assembly 48.
- the bearing assembly 46 may be positioned with a nut 30 and a bevel gear 28 for securing the bearing assembly 46 from axial movement.
- the bearing assembly 46 may be clamped by a nut 30 to the shaft 16.
- the centering support 26 may circumscribe the outer race 20 of the bearing assembly 46.
- the centering support 26 may be comprised of a material, such as steel, aluminum, or titanium.
- the centering support 26 may be seen in isolation in Figure 2.
- the centering support 26 may comprise exterior bumpers 32 along an outer surface 42 of the centering support 26 and interior bumpers 34 along an inner surface 44 of the centering support 26.
- the exterior bumpers 32 may be situated within the bearing support housing 14 (shown in Figure 1) with an interference fit.
- the interior bumpers 34 may be ground (for example, by a grinding machine) to provide a vertical offset of a shaft 16 (shown in Figure 1) centerline to accommodate deflection due to the weight of the shaft 16. This offset feature permits the turbomachine to operate concentric to the centerline of the bearing support housing 14.
- Tangential grooves 36 may be cut into the exterior bumpers 32 to permit oil passage during ring deflection so that oil may be squeezed outward to add additional viscous damping to the squeeze film damper 24.
- Each groove 36 may be perpendicular to the respective exterior bumper 32 and each groove 36 may be parallel to a direction of rotation of the shaft 16.
- Figure 3 shows an enlarged view of Section A of Figure 2.
- An exterior bumper height 38 may be measured from the outer surface 42 of the centering support 26 to the distal end of the exterior bumper 32.
- the exterior bumper 32 may have an exterior bumper height 38 from about 0.006 inch (0.01524 cm) to about 0.008 inch (0.02032 cm).
- the exterior bumper height 38 may be from about 0.006 inch (0.01524 cm) to about 0.008 inch (0.02032 cm).
- An interior bumper height 40 may be measured from the inner surface 44 of the centering ring 26 to the distal end of the interior bumper 34.
- the interior bumper 34 may have an interior bumper height 40 of about 0.007 inch (0.01778 cm).
- the interior bumper 34 may have an interior bumper height 40 from about 0.00745 inch (0.01892808 cm) to about 0.007785 inch (0.008702 cm).
- a method 300 for rotatably supporting a rotor assembly with a support structure 12 may comprise a step 310 of mounting a bearing assembly 46 for supporting a shaft 16 within a movable member.
- a step 320 may comprise suspending the movable member from the support structure 12 upon at least two bearing assemblies 46.
- a step 330 may comprise establishing a squeeze film damper between the movable member and the support structure 12 and a step 340 may comprise centering the movable member with a centering support 26, wherein the centering support 26 may comprise exterior bumpers 32 and interior bumpers 34.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Aviation & Aerospace Engineering (AREA)
- Support Of The Bearing (AREA)
Abstract
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/967,979 US20060083448A1 (en) | 2004-10-19 | 2004-10-19 | Compact compliant centering support for squeeze film damper |
PCT/US2005/037480 WO2006044913A1 (en) | 2004-10-19 | 2005-10-19 | Compact compliant centering support for roller bearing having squeeze film damper |
Publications (1)
Publication Number | Publication Date |
---|---|
EP1802849A1 true EP1802849A1 (en) | 2007-07-04 |
Family
ID=36180826
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP05811866A Withdrawn EP1802849A1 (en) | 2004-10-19 | 2005-10-19 | Compact compliant centering support for roller bearing having squeeze film damper |
Country Status (4)
Country | Link |
---|---|
US (1) | US20060083448A1 (en) |
EP (1) | EP1802849A1 (en) |
CA (1) | CA2584727A1 (en) |
WO (1) | WO2006044913A1 (en) |
Families Citing this family (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20060204153A1 (en) * | 2005-03-10 | 2006-09-14 | Honeywell International Inc. | Compact resilient anisotropic support for bearing |
US8118570B2 (en) | 2007-10-31 | 2012-02-21 | Honeywell International Inc. | Anisotropic bearing supports for turbochargers |
US8337090B2 (en) * | 2009-09-10 | 2012-12-25 | Pratt & Whitney Canada Corp. | Bearing support flexible ring |
US8834095B2 (en) * | 2011-06-24 | 2014-09-16 | United Technologies Corporation | Integral bearing support and centering spring assembly for a gas turbine engine |
US9500231B2 (en) * | 2011-09-30 | 2016-11-22 | Williams International Co., L.L.C. | Fractured-outer-race full-complement ball-bearing system incorporated in a turbocharger assembly |
DE112015002605B4 (en) * | 2014-06-02 | 2022-09-01 | Ihi Corporation | Bearing assembly and turbocharger |
JP6605253B2 (en) * | 2015-08-07 | 2019-11-13 | 株式会社東郷製作所 | Tolerance ring |
US9745992B2 (en) | 2015-08-30 | 2017-08-29 | Honeywell International Inc. | Turbocharger bearing damper assembly |
US9702404B2 (en) | 2015-10-28 | 2017-07-11 | United Technologies Corporation | Integral centering spring and bearing support and method of supporting multiple damped bearings |
US10550849B2 (en) * | 2016-12-12 | 2020-02-04 | Garrett Transportation I Inc. | Turbocharger assembly |
US11391217B2 (en) | 2019-10-03 | 2022-07-19 | Rolls-Royce Corporation | Stiffening member for epicyclical gear system housing assembly |
US20210102616A1 (en) * | 2019-10-03 | 2021-04-08 | Rolls-Royce Corporation | Bearing spring for epicyclical gear system housing assembly |
US11353089B2 (en) * | 2019-10-03 | 2022-06-07 | Rolls-Royce Corporation | Epicyclical gear system housing assembly |
Family Cites Families (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1386255A (en) * | 1919-04-29 | 1921-08-02 | John George William Gruban | Roller, ball, and other bearing |
US3053590A (en) * | 1957-06-24 | 1962-09-11 | Shaft seal | |
DE1482737A1 (en) * | 1965-06-28 | 1969-11-27 | Salzgitter Maschinen Ag | Device for damping the oscillating movements of centrifuge drums, in particular sugar centrifuge drums |
US4527912A (en) * | 1984-05-31 | 1985-07-09 | General Motors Corporation | Squeeze film damper |
US4781077A (en) * | 1986-12-19 | 1988-11-01 | Massachusetts Institute Of Technology | Stable intershaft squeeze film damper |
US4828423A (en) * | 1987-04-06 | 1989-05-09 | Cramer Jr Arthur A | Tolerance ring and shim |
US4867655A (en) * | 1988-03-14 | 1989-09-19 | United Technologies Corporation | Variable stiffness oil film damper |
US4947639A (en) * | 1988-05-12 | 1990-08-14 | United Technologies Corporation | Apparatus and method for supporting a rotating shaft in a rotary machine |
US4981415A (en) * | 1989-08-16 | 1991-01-01 | United Technologies Corporation | Support for oil film dampers |
US4992024A (en) * | 1989-12-13 | 1991-02-12 | Allied-Signal Inc. | Multi-film fluid bearing damper |
US5067825A (en) * | 1990-06-18 | 1991-11-26 | Vance John M | Aircraft engine rotor squeeze film damper |
US5909705A (en) * | 1996-07-08 | 1999-06-08 | The Minster Machine Company | Vacuum seal for slide guiding |
US5791789A (en) * | 1997-04-24 | 1998-08-11 | United Technologies Corporation | Rotor support for a turbine engine |
US6220829B1 (en) * | 1998-10-05 | 2001-04-24 | Glenn F. Thompson | Turbocharger rotor with low-cost ball bearing |
US6325546B1 (en) * | 1999-11-30 | 2001-12-04 | General Electric Company | Fan assembly support system |
US6557457B1 (en) * | 1999-12-01 | 2003-05-06 | Federal-Mogul World Wide, Inc. | Bushingless piston and connecting rod assembly and method of manufacture |
EP1174629A1 (en) * | 2000-06-30 | 2002-01-23 | Techspace Aero S.A. | Sealing device of a squeeze film damper incorporated in a rolling element bearing |
US6682219B2 (en) * | 2002-04-03 | 2004-01-27 | Honeywell International Inc. | Anisotropic support damper for gas turbine bearing |
US6640784B1 (en) * | 2002-10-09 | 2003-11-04 | Robert Bosch Corporation | Spark ignition direct injection system |
US7052183B2 (en) * | 2004-06-15 | 2006-05-30 | Honeywell International Inc. | Composite resilient mount |
-
2004
- 2004-10-19 US US10/967,979 patent/US20060083448A1/en not_active Abandoned
-
2005
- 2005-10-19 EP EP05811866A patent/EP1802849A1/en not_active Withdrawn
- 2005-10-19 CA CA002584727A patent/CA2584727A1/en not_active Abandoned
- 2005-10-19 WO PCT/US2005/037480 patent/WO2006044913A1/en active Application Filing
Non-Patent Citations (1)
Title |
---|
See references of WO2006044913A1 * |
Also Published As
Publication number | Publication date |
---|---|
CA2584727A1 (en) | 2006-04-27 |
WO2006044913A1 (en) | 2006-04-27 |
US20060083448A1 (en) | 2006-04-20 |
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Legal Events
Date | Code | Title | Description |
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PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 20070418 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): DE FR GB |
|
17Q | First examination report despatched |
Effective date: 20070711 |
|
RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: CHARLESTON, SHARI, L. Inventor name: JOHNSON, MATTHEW, D. Inventor name: TALBERT, PAUL, B. Inventor name: JANKOWICH, EDWARD, M. Inventor name: SPENCER, DOUG, K. Inventor name: MOHSIUL, ALAM |
|
DAX | Request for extension of the european patent (deleted) | ||
RBV | Designated contracting states (corrected) |
Designated state(s): DE FR GB |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
18D | Application deemed to be withdrawn |
Effective date: 20100504 |